http://www.ispreview.co.uk/index.php/2013/04/scientists-deliver-3gbps-capable-high-speed-internet-from-ceiling-lamps.html
Researchers working at the Fraunhofer Heinrich Hertz Institute in Berlin (Germany) have taken their Visible Light Communication (VLC) technology, which makes it possible to use standard “off-the-shelf” LED (Light-Emitting Diode) room lights for data transmission, to the next level by boosting the speed up to 3Gbps (Gigabits per second).
Back in 2011 the same scientists succeeded in creating an 800Mbps (Megabits per second) capable network using a similar method of flashing LED lights (here) and the latest development appears to be an extension of that effort, which could potentially deliver a new kind of seamless “Optical WLAN” (Optical Wireless Local Area Network) for home, office and even public environments.
A complete real-time system has already been exhibited at trade fairs, which reached an impressive data throughput of 500Mbps (Megabits per second), but the latest patent protected components have, in lab experiments, now pushed this into Gigabit territory.
Apparently the new components have achieved a transmission rate of 1Gbps per single light frequency, which can be extended to 3Gbps because off-the-shelf LEDs typically use up to three light frequencies (RGB – Red, Green and Blue). Previously the same LEDs could only be used with a bandwidth of around 30MHz but the latest ones have pushed this to 180MHz.
HHI Statement
“Development of the components as modules makes them suitable for customized integration in technology developments such as Car-to-X communication. But visible light communication also has a broad array of other possible applications ranging from areas like hospital operating theatres where safety is at a premium to places like trade shows and factory halls where radio communication is problematic. This new development represents a major step forward towards optical high-speed WLAN.”
The cheap LEDs, which could for example be placed on the ceiling or in room lights and tend to have coverage of around 10 meters, essentially blink on and off extremely fast to transmit the data (not visible to your naked eye). This would make it extremely useful for short range and high-speed networks that may also require something more secure than wifi (i.e. light doesn’t travel so well through solid walls etc.).
It should however be said that researchers from the University of Strathclyde in Scotland (UK) are also working on a similar Light Fidelity (Li-Fi) technology that uses micron-sized LEDs, which could be installed in everything from desktop monitors to smartphones (here).
In fact there are a number of teams working to harness the capabilities of LED lighting for communication networks and some of these are now just starting to move into the early commercial development stages. HHI’s new components will soon be presented at FOE 2013 in Tokyo.